Not Applicable
Not Applicable
1. Field of the Invention
This invention relates to the disk drive suspensions having limiters against undue movement of the slider-carrying tongue from the suspension beam portion. In a particular aspect, the invention provides a reduced vertical extent limiter structure that effectively blocks slider contact with the opposing disk upon shock events and the like.
The invention achieves limited vertical extent in the limiter structure by using the space already dedicated to the slider and tongue and no more except for the limit gap to provide a limiter structure that does not increase the vertical profile of the suspension. The invention is thus especially useful in the most compact head disk assemblies.
2. Description of the Related Art
Numerous limiters have been proposed and many are in use. In general, all limiters constrain some movement of the tongue-carried slider by stopping unwanted tongue movement against the beam portion or the flexure itself using an added element that traverses the space between the tongue and the flexure or beam portion. Known limiters increase the overall height of the suspension assembly by using elements that project out of the plane of the suspension, e.g. above (or below) the flexure or beam portion to engage the same.
It is an object of the present invention to provide an improved head disk assembly. It is a further object to provide a head disk assembly suspension with a limiter feature but within the original plane of the suspension, useful in microactuated and other suspensions. It is another object of the invention to provide a limiter structure and limiter method that use the space already dedicated to the tongue and slider for locating the limiter structure. Another object is the provision of a limiter structure that projects out of the plane of the beam portion toward the tongue free end and that blocks the undue movement of the tongue beyond a predetermined gap, the limiter structure having a vertical extent no greater than the combined vertical extents of the tongue free end, the slider and the predetermined gap. Other objects include providing supplementary limiters on the flexure frame, a dimple defined by an etched and deflected part of the beam portion, and a front end lifter formed on the beam portion.
These and other objects of the invention to become apparent hereinafter are realized in a disk drive suspension adapted for low profile head disk assemblies with limited vertical space, the suspension comprising a base portion, a spring portion, and a beam portion, a flexure supported by the beam portion and having a frame and a tongue extending from the frame to have a free end opposite a locus on the beam portion at a predetermined gap, a slider carried by the tongue free end, the beam portion, the gap and the slider having a combined vertical extent, a low profile limiter structure at the locus, the limiter structure being sized to not exceed in its vertical extent the combined vertical extent, the free end defining cooperating structure that interengages with the limiter structure against undue travel of the free end relative to the beam portion.
In this and like embodiments, typically, the flexure is separately formed from the beam portion and fixed thereto, the gap is about 0.002 inch in vertical extent, the limiter structure does not exceed about 0.004 inch, the limiter structure has a shank portion and a head extending outward from the shank portion, the shank portion passing the cooperating structure in head interengageable relation with the free end, the limiter structure comprises a tab, and the cooperating structure comprises a slot intermitting with the tab in free end engageable relation with the tab, the beam is etched at the locus to define the limiter structure, the locus is generally rectangular, the locus being etched to define a hook-shaped limiter in the plane of the beam portion, the limiter structure being bent from the plane of the beam portion to intersect the plane of the free end in cooperating structure engageable relation, the hook-shaped limiter is T-shaped, the beam portion defines an edge shoulder, the flexure defining a cooperating projection rearward of the free end terminus that engages the edge shoulder in free end movement limiting relation, the beam portion further defines left and right edge shoulders, the flexure defining cooperating projections rearward of the free end terminus that engage the edge shoulders in flexure or free end movement limiting relation and/or the load beam is etched to define a dimple opposite the slider.
In a further embodiment the invention provides a suspension as described and in which the flexure has an open frame, and a tongue cantilevered from the frame to have a free end opposite a locus on the beam portion, the free end having an outer terminus, a slider carried by the tongue free end inward of the outer terminus, a low profile limiter structure comprising a tab separated on three sides from the beam portion and extending from the beam portion locus toward the free end, the tab having a projecting shoulder spaced at a gap from the beam portion, the free end outer terminus having an opening that interfits with the tab in tab shoulder engaging relation to block free end movement away from the locus beyond that permitted by the gap.
In this and like embodiments, typically, the foregoing features are provided and the flexure is formed separately from the beam portion, and is disposed in an adjacent plane generally parallel with the beam portion plane, the flexure frame has left and right outriggers and a cross-member therebetween surrounding an opening, the tongue being cantilevered from the cross member to extend into the opening, the limiter structure has a shank portion and a head extending outward from the shank portion, the shank portion passing the cooperating structure in head interengageable relation with the free end, the limiter structure comprises a tab, and the cooperating structure comprises a slot interfitting with the tab in free end engageable relation with the tab, the beam portion is etched at the locus to define the limiter structure, the beam portion defines an edge shoulder, the flexure defines a cooperating projection rearward of the free end terminus that engages the edge shoulder in free end movement limiting relation, or the beam portion further defines left and right edge shoulders, the flexure defining cooperating projections rearward of the free end terminus that engage the edge shoulders in free end movement limiting relation.
In its method aspects the invention provided a method of blocking in a head disk assembly undue movement beyond a predetermined gap of a flexure tongue and slider away from the beam portion of a suspension without increasing the vertical extent of the suspension, including deflecting from the beam portion and opposite the longitudinal axis of the tongue a limiter structure having a shape that predetermines the gap, limiting the vertical extent of the limiter structure to not greater than the combined vertical extent of the beam portion, the slider and the gap, and interengaging the limiter structure with the tongue against tongue movement greater than allowed by the gap.
In this and like embodiments, typically, the method also includes etching the limiter structure from the beam portion on three sides to have a hook shape in its deflected condition, selectively engaging a lateral region of the flexure tongue with an opposing lateral region of the beam portion at one or more locations spaced from the limiter structure upon undue movement of the tongue from the beam portion, and also defining a dimple in the beam portion between opposed lateral regions thereof to engage the tongue portion in slider gimballing relation.